Meanwhile, for Rarebit Sauce, in a medium saucepan heat milk and margarine or butter over medium heat. Gradually add hot milk mixture into beaten egg yolks, stirring constantly; stir in mustard and red pepper. Return mixture to saucepan. Continue to heat, stirring constantly, until mixture coats a metal spoon. Stir in cheese
, a handful at a time, stirring until melted after each addition. when all cheese has been added, continue to heat for 1 to 2 minutes more or until smooth, stirring constantly; do not boil.